2011 (SBTE) 25th Annual Meeting Proceedings - International ...

Acta Scientiae Veterinariae, 2011. 39(Suppl 1): Abstracts - 25th Annual Meeting SBTE-Brazil. August 2011.
A185 EMBRYOLOGY, BIOLOGY OF DEVELOPMENT AND PHYSIOLOGY OF REPRODUCTION
EFFECTS OF OXYGEN
TENSION AND GLUC
UCOSE CONCENTR
ONCENTRATION TION DURING IN VITRO MATUR
TURATION TION OF BOVINE
OOCYTE ON OOCYTE QUALIT
ALITY AND MATUR
TURATION TION AND EMBRYONIC DEVEL
VELOPMENT
Gisele Zoccal Mingoti 1 , France Filion 2 , Lawrence Charles Smith 2 & Patrick Vincent 2
1
UNESP, ARAÇATUBA, SP, BRAZIL. 2 UNIVERSITE DE MONTREAL, ST-HYACINTHE, CANADA.
Aiming to avoid the production of free radicals during IVP of bovine embryos and consequently improve the production and quality
of embryos, this study evaluated the effects of O2 tension and addition of glucose during IVM on bovine oocyte nuclear and cytoplasmic
maturation (assessed by the cytoplasmic distribution and mitochondrial DNA quantification - mtDNA) and embryonic development. Oocytes
were IVM in mSOF (Soto & Smith, Mol Reprod Dev 76:637-46, 2009) with hormones for 24 h at 38.5ºC. Depending on the experimental
group, glucose was added to the medium at concentrations of 0.48 mM or 5.6 mM (high glucose concentration - 20 mM - was also tested during
the nuclear and cytoplasmic maturation, but there was no difference from 5.6 mM and it was not used in subsequent experiments). Oocytes were
IVM under high (~20% -atmospheric) or low (5%) O2 tension. Afterwards, oocytes (n = 248) were stained with 10 µg/mL of MitoTracker
Green (to evaluate the mitochondrial distribution) and 10 µg/mL Hoechst 33342 (nuclear maturation assessment). The mtDNA number of copies
was measured in individual oocytes (Soto & Smith, Mol Reprod Dev 76:637-46, 2009, n = 20). Other oocytes (n = 453) were IVF and the
zygotes were IVC in mSOF; the blastocyst (Bl) rates were assessed at 168 hpi. Means were compared by ANOVA followed by Tukey’s test (P
< 0.05). The proportion of MII oocytes was not affected by glucose concentration (P > 0.05), but it was affected by O2 tension (20%: 86.1%
vs. 5%: 67.4; P < 0.05). The mitochondrial cytoplasmic redistribution (disperse = mature) was not affected by O2 tension (20%: 55.0% vs. 5%:
56.2%; P > 0.05) or glucose (0.48 mM: 54.4% vs. 5.6 mM: 54.2%; P > 0.05). There was no effect of O2 tension (20%: 46.8×104 vs. 5%:
43.2×104; P > 0.05) or glucose (0.48 mM: 39.2×104 vs. 5.6 mM: 49.2×104; P > 0.05) on mtDNA copy number. Embryonic development to
Bl stage was unaffected by O2 tension (20%: 10.4% vs. 5%: 11.9%; P > 0.05) or glucose (0.48 mM: 11.2% vs. 5.6 mM: 11.0%; P > 0.05).
However, there was effect of O2 tension (20%: 83.4% vs. 5%: 136.2; P < 0.05) on the total number of Bl cells, but no effect of glucose
concentration was observed (0.48 mM: 109.3 vs.. 5.6 mM: 98.3; P > 0.05). There was no effect of O2 tension (20%: 7.2% vs. 5%: 5.5%; P >
0.05) or glucose (0.48 mM: 7.2% vs. 5.6 mM: 5.8%; P > 0.05) on percentage of TUNEL+ cells in Bl. In conclusion, in vitro oocyte maturation
under low O2 tension reduces the proportion of nuclear maturation, but does not affect the cytoplasmic maturation and embryonic development,
and increases the total number of cells in the blastocysts.
Keywords: in vitro maturation, mitochondria, embryo development.
A186 EMBRYOLOGY, BIOLOGY OF DEVELOPMENT AND PHYSIOLOGY OF REPRODUCTION
FLORFENIC
ORFENICOL OL AND SODIUM CLOPR
OPROSTENOL OSTENOL FOR THE TREATMENT OF RETAINED PLACENT
CENTA IN DAIRY COWS
A namara a Per
ereir
eira 1 , M iller Per
ereir
eira Palhão
1 , Br uno Fer
ernandes Ludger
udgero Alv
lves
2 , Eduar
duardo do Ramos de Oliv
liveir
eira 2 , Ta timara a Mar
aria Miy
iyauchi
2 ,
Thais Camargo Rossi 1 , Jose Antonio D. Garcia 1 & Carlos Antônio de Carvalho Fernandes 1
1
UNIFENAS, ALFENAS, MG, BRAZIL. 2 BIOTRAN, ALFENAS, MG, BRAZIL.
N
Retained placenta (RP) is considered a pathologic condition when fragments or total fetal membranes remained attached for more
than 12h after calving. A variety of risk factors include early or induced parturition, dystocia, hormonal imbalances and immunosuppression.
This disease has several implications for reproductive efficiency in dairy farms. It is close related to postpartum uterine infection, to delay the
ovarian activity and the uterine involution after parturition, and to decreased fertility after artificial insemination (AI). The aim of this study was
to compare the reproductive efficiency in dairy cows with RP and treated with Florfenicol associated or not with Cloprostenol. Hundred-eight
cows with RP, from dairy herds in southern of Minas Gerais and northern of São Paulo state, were included for this purpose. The experiment
was arranged in factorial 2X2. The four treatments encompassed two levels of each factor: 1) Florfenicol - 40 mg/kg (IM) divided in two
injections - 20 h after calving (20 mg/kg) and 48 h after the first (20 mg/kg) - or 40 mg / kg (SC) - one injection 20 h after calving; 2) Cloprostenol
(0.530 mg) - one injection associated with each florfenicol treatment - or without cloprostenol. The variables assembled for this design were the
intervals from parturition to AI (P/IA) and to conception (P/C), and the number of services per conception (S/C). The percentage of animals with
corpus luteum (CL) between 25 and 40 days postpartum were also evaluated. The data were submitted to ANOVA and means of continuous
variables were compared by Tukey test (P < 0.05). The distributions of frequency were compared by c2 (chi square). A total of 579 parturitions
were evaluated to accomplish 108 animals with RP. Thus, the overall occurrence of RP was 18.6%. There were no significant differences
between treatments for any analyzed variable. The overall mean for P/IA, P/C and S/C were 65.1±17.5 d, 3.0±1.0 and 154.6±42.0 d,
respectively. The percentage of animals with CL did not differ between treatments (P > 0.3), and 55.6% (60/108) of cows had CL between 25
and 40 days postpartum. Combining treatments in two groups according to cloprostenol injections – with cloprostenol or without cloprostenol
– the interval from parturition to AI was different (P < 0.05) between groups (59.2 ± 16.9 vs. 70.8 ± 18.3 d, respectively). It is concluded that
the route of administration of florfenicol did not influence the reproductive performance of postpartum dairy cows in postpartum, however,
cloprostenol reduced the interval from calving to first AI. [Support: FAPEMIG].
Keywords: reproductive eficiency, puerperium, uterine involution.
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